Integration By Parts
by amiasha
Summary: It's been six years since the defeat of BelialVamdemon, and with the Digital World seemingly at peace the Chosen are focused on living their lives as normally as is possible for them. However, there are other dimensions far less stable than the Digital World, and the borders between the planes are weakening…


**Notes** : My first major fanfiction in… Uh… Years? But Digimon sucked me back in, and so I'm giving this fic thing a shot once again. Please feel free to leave me comments or message me! I want to know what you think.

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"We're going to be late."

Taichi looked up from his shoelaces to fake glower at Koushirou for a few seconds in response, returning his attention to what he was doing. "Stop nagging; we've got time. You don't even want to go, so what's the rush?"

Koushirou sipped his energy drink for a moment, clearly unimpressed by the question, before deciding to go ahead and answer it anyway. "It's mandatory, Taichi. Not wanting to attend doesn't mean we can simply not do so."

"Yeah, yeah, you've said that." Taichi complained in response, straightening up and stepping forward to pluck the can out of Koushirou's hand. He earned a blink of surprise and then a wordless sputter of offense from his friend in return, both of which were promptly ignored. "Aren't you supposed to stop drinking these?"

"I'm supposed to drink less of them." Koushirou admitted, tugging gently on the can which Taichi relinquished dubiously.

"It's 7:30 AM."

"I'm aware of that. That's why we're going to be late."

Taichi sighed loudly and rolled his eyes but decided to let it go for then, especially as Koushirou had managed to turn the conversation back to their impending deadline. "Fine, whatever. Let's go get this over with."

The two gathered up their school bags and stepped out of the dorm, Koushirou waiting a few steps down the hall for Taichi to lock the door and catch up before they continued toward the stairs. It wasn't a long walk from their dorm to the building that was holding the seminar they were supposed to attend, so Taichi still wasn't convinced they were late, but part of being a good leader was knowing when to pick his battles.

They continued in silence, Taichi mentally planning out the day while Koushirou typed on his iPhone with one hand and kept sipping his energy drink with the other. They had this seminar first, along with—presumably—Yamato, Sora, and Mimi, and then all five would go separate ways for classes. Fortunately Taichi had no work that day, but he needed to call Hikari after class to check in with her on the outreach program for newly partnered Digimon pairs. It had been six years since the younger team of Chosen had defeated BelialVamdemon, but after the first several months the rate at which individuals had been being matched with Digimon had slowed down. There were still plenty of people, even after six years, that were just finding their teammates.

The Yagami siblings handled much of helping out these new pairs, Taichi primarily dealing with older individuals and Hikari with children. That meant Hikari did the majority of the work, but Taichi still had his hands full when combined with all of his other responsibilities. Being a full time university student wasn't easy, after all.

It had been worse the first year, though, while Koushirou was finishing high school; Taichi hadn't been alone—Yamato and Sora had started at Keio University the same year he had—but his first year he'd been paired up with a randomly selected roommate, and it had been something of a disaster. Taichi considered himself pretty easy-going and he generally got along with almost everyone he met, but he'd been ready to murder his roommate after half a week and the feeling had been mutual. It had been a tense and awkward couple of semesters, and Taichi couldn't have been more relieved when Koushirou said he was turning down his acceptance to Tokyo University—where Jyou was studying medicine—to attend Keio University instead.

Spring semester had just started the week before and Taichi steadfastly maintained it should really be called Winter semester; this belief was only reaffirmed when he and Koushirou stepped out of the dorm to a blast of icy wind and the crunch of a thin layer of ice covering the sidewalk.

"Nice day out." Taichi commented, earning a dry look from Koushirou in response, which he countered with a grin as he stepped fearlessly onto the ice. "Hey, I'll race you."

"No, Taichi." Koushirou said, his tone a perfect blend of polite and long-suffering that Taichi was still not sure how was possible. He supposed after all this time of having him for a best friend it was only natural Koushirou could manage a blend of politeness and whatever exasperated emotion he felt at the time, and ultimately Taichi was just glad Koushirou had finally, finally dropped the "–san" honorific from his name.

It had only taken nearly ten years.

"Fine, fine. But someday we're going to have an ice race." Taichi responded, passing Koushirou—who was walking carefully on the ice, probably so he wouldn't slip and drop his ridiculously expensive phone—to lead the way toward the corner. A familiar pair of twenty-year olds were waiting for them, Sora's orange hair shimmering in the one patch of sunlight that peeked out from behind the clouds, Yamato's blond hair in contrast mostly hidden under a black knit beanie. Taichi had teased him about the hat before, but Yamato insisted that beanies were cool and that Taichi was just jealous he couldn't fit his own hair into a hat.

The scene caused by that exchange was immortalized forever in the pictures Mimi had immediately posted on the internet. It turned out Yamato was right about Taichi's hair not fitting in a hat after all.

"Hey! Ready to go?" Sora asked once Taichi and Koushirou had reached them, offering a smile at them both before her lips suddenly curved into a frown in Koushirou's direction and she gave the can he was holding a pointed look.

"I told you." Taichi informed Koushirou before brushing by to talk to Yamato, ignoring the beginning of Sora's lecture and Koushirou's lame protests in favor of addressing his friend. "How many classes have you got today, Yamato?"

"Just two, besides this seminar." Yamato responded, similarly ignoring his girlfriend and Koushirou, beginning down the sidewalk toward Mimi's dorm. "Physics at ten, then Anthropology at one. You?"

"I've got two also, but the first one isn't until twelve." This stupid mandatory informational session was completely inconvenient, which only added to the annoyance of having to attend it in the first place. Taichi wasn't even sure what it was about; some sort of informational session for people living on campus. Probably teaching them how to do laundry or something.

He glanced back as Koushirou and Sora caught up, the former now down one energy drink and seemingly sulking a little bit even as Sora was promising to buy him a coffee instead once they got to campus. Taichi rolled his eyes in fond exasperation before returning his attention to Yamato again, who gave a small noise of amusement before responding to Taichi's previous comment. "Are you sharing classes with any of us this semester?"

"I think I have one with Mimi." Taichi responded, nodding. Mimi wasn't sure yet of her major and so was getting her general education classes out of the way, one of which Taichi hadn't taken yet. Some writing class that Taichi wasn't sure he was all too excited about having to do but couldn't get out of. "Composition or something."

Yamato nodded thoughtfully, but before he could offer a response they were joined by a pastel pink blur of a Chosen Child. Mimi grinned at them, her winter coat the source of the influx of pink, and her long honey hair streaked with snow white extensions. She seemed totally unbothered by the weather or the early hour, cheerful as ever. "Hey guys!"

"Hey, Mimi." Taichi grinned back, the enthusiasm contagious, at least for him. The quieter three of their group offered greetings as well, just not as enthusiastically, which didn't seem to faze Mimi any more than the weather did. "Ready for… Whatever this thing is?"

"Of course I am. They're offering free breakfast!" Mimi responded, as if that were the entire point of the class in the first place. Now that this information was revealed, Taichi was inclined to agree.

"There's gonna be food?" He asked, suddenly a whole lot more into this whole idea. "I didn't know that!"

He pointedly ignored Yamato's mutter to Sora and Koushirou of, "Some things never change." It was hard to take seriously when he knew Yamato was not-so-secretly pleased by the idea of food as well.

The five of them chattered the rest of the walk to campus and as they looked for the correct building, only quieting once they found the packed lecture hall. They only had a few minutes before the seminar would start—Koushirou had been right to be concerned about being late, no surprise there—but fortunately there was not only the promised breakfast but even some food left. They'd have to split up to find seats, but at least they had donuts and coffee.

"You know, that's just bad as the energy drink thing." Taichi commented as he gathered up four donuts, his words addressed toward Koushirou. Yamato, Mimi, and Sora had all quickly snagged some food and found seats, but Taichi was being picky about donuts and Koushirou seemed intent on drinking the entire carafe of coffee.

Koushirou gave him a look around the paper coffee cup he was chugging from, finishing the coffee and refilling it again. Taichi was pretty sure that was cup three, and so once it was full Taichi grabbed the shoulder of Koushirou's coat and began steering him toward an empty pair of seats near the back. "Here, have some food with your caffeine, at least." He added, shoving a donut at the redhead before taking his own seat and starting on a donut as well.

This time the look Koushirou gave him was actually followed up by a response, although it was quiet one so their classmates wouldn't overhear. "You don't need to worry so much."

Taichi was quiet a moment in return, the corner of his mouth tugging into a frown and his donuts temporarily forgotten, but he decided to let it go for then as a speaker stepped up onto the stage to begin whatever this lecture was supposed to be about. He and Koushirou lived together, so they could take up this conversation again later.

His guess of the seminar being about laundry wasn't terribly far off. It was some sort of "campus living" thing, going over the basics of balancing a checkbook and cooking meals and other similar nonsense that Taichi was pretty sure was meant for people that hadn't survived several months in another world when they were elementary students. Koushirou seemed to share his sentiments, judging from the fact that he was scrolling through something on his iPhone rather than paying any attention, and Taichi just sighed and returned to his donuts. At least he got something out of this waste of time.

The lecture seemed to drag on forever and Taichi was on the verge of falling asleep in his chair when the sound of thunder jolted him back fully to awareness. Koushirou seemed similarly startled, as did most of the hall, including the speaker who had paused his droning on reflex.

"Thunder snow?" Taichi asked, after a moment, and Koushirou nodded with furrowed eyebrows.

"Probably, yes." It wasn't a super rare phenomena or anything, but still unexpected. Taichi learned over his friend's shoulder as Koushirou began pulling up the radar on his phone, while the lecturer returned to rambling.

It didn't last long as there was soon another boom of thunder, accompanied by the lights flickering once before going out completely. Phones lit up immediately around the hall, as well as a few mini flashlights, including the one on Taichi's keychain which he panned around to see if he could spot wherever Yamato, Sora, and Mimi had chosen to sit.

"Stay calm, everyone." The lecturer said, although he didn't sound all that calm himself. "There seems to be a storm going on, but I'm sure the power will only be out a short time."

"Right." Taichi muttered, unimpressed, completely ignoring the speaker just as the rest of the hall was. He caught sight of Sora with Yamato down near the front of the hall and Mimi in the row behind the pair, leaning over the back of their seats to talk to them. Satisfied that he knew where they were, Taichi glanced back at Koushirou again. "Got the radar up?"

Koushirou shook his head, eyebrows furrowed. "No. I don't have any service, probably from the storm."

This just got better and better. Oh well, they didn't need a radar to see how the weather looked when they had windows, and Taichi moved to get to his feet.

"Where are you going?" Koushirou asked, but he was already moving to follow Taichi without waiting for the answer. He'd probably already figured it out, but Taichi answered anyway.

"To take a look outside. There's no point in sitting here in the dark." He said, leading the way toward the doors and joined by several other students who had the same idea. The lecturer gave a half-hearted attempt to stop them, but then just settled with asking them to come back into the room once the lights turned back on.

It was just as dark in the rest of the building as it was in the lecture hall, but that was even more ominous considering there were several large glass windows that should've been letting light in, even with a storm going on. Instead it looked almost like night, the windows rattling with the wind and a mixture of hail and sleet.

"Stay away from the windows." Koushirou said, correctly predicting Taichi's plan of getting close enough to more or less smash his face against the glass. Taichi was tempted to do so anyway, wanting to get a better look at the sky, but hung back for the moment as Koushirou continued. "The storm looks really strong…"

Taichi nodded in agreement, but he knew from Koushirou's tone that the redhead was thinking the same thing he was; something wasn't quite right. "It's too dark."

Koushirou nodded as well, about to respond when Yamato stepped up beside them along with Sora and Mimi. It was clear from their flashlight-lit expressions that they felt the same way as Taichi and Koushirou, although Mimi was the first to say it. "Is it just me, or does it look like more than just a storm?"

"If it's not just a storm then what is it?" Sora asked, but it was clear from her tone that she wasn't actually objecting to Mimi's words.

Before anyone could answer there was a blinding flash of lightning and an almost instantaneous boom of thunder, the windows shaking again from the force of it. Yamato frowned in concern, beginning to echo Koushirou's previous words. "I think we should stay away from—"

The windows shattered in a sudden crash, glass spraying through the halls, followed immediately by wind and sleet. Taichi pulled Koushirou and Mimi toward him on reflex, trying to shield them from the worst of the glass as Yamato did the same with Sora, and as soon as it had blown over he raised his voice over the wind to ask if everyone was okay. He was met with a round of affirmatives, a few scratches here and there but the worst of it stopped by their thick coats and, somewhat humorously, Yamato's beanie. The blond pulled a large piece of glass out of his hat with an irritated scowl and dropped it to the ground in disgust.

The storm hadn't been quiet before, but without the windows it was as if a hurricane was upon them, and Taichi suddenly wondered if that wasn't exactly what it was. The yelling of other students didn't help, but there was reason for the yelling as several people had been cut by the shattered windows. He scanned the crowd quickly, looking for anyone who might need immediate help, but luckily it seemed everything was superficial and most of the students were already rushing back into the lecture hall to avoid the sleet.

Taichi ushered his team in after them, pulling the heavy doors shut behind them; that blocked out the sleet and some of the noise, but it was almost as loud in the large room from just the other students' voices. The lecturer was trying futilely to calm everyone, but he was just as lame as he had been before and Taichi could only listen to a few seconds of sputtered reassurances into the battery-powered microphone before he couldn't take any more of it.

"I'll be right back." He told the other Chosen, getting nods in return before he began shoving past other students to get to the stage. The lecturer seemed stunned by his sudden appearance, and Taichi took the opportunity to liberate the microphone from his grasp without a word. Instead Taichi addressed the other students, his commanding voice echoing through the room even over another crack of thunder.

"Hey, everyone, stay calm. We're all safe in here. Is anyone seriously hurt?" The students, which had gone generally quiet at the sound of Taichi's voice, stayed so after the question; Taichi took that as a no when combined with the shaking heads he could make out in the dark. "Okay, good. Everyone just chill out until the storm dies down." He paused a moment after the order before adding with a grin, "Maybe classes'll be cancelled."

"They better be!" Someone shouted from the crowd, earning some nervous laughter from the other students, and with his job done Taichi shoved the microphone back into the lecturer's hands before leaving the stage to return to the other Chosen.

"Couldn't resist, could you." Yamato asked, not really as a question, and not actually as disapproving as his tone might suggest.

"Someone had to do something." Taichi offered in return, shrugging and picking a piece of glass out of his coat. "Guess the teacher wasn't as prepared for campus living as he thought."

That earned a snicker from Mimi and an amused eyeroll from Sora, which was about as much approval as Taichi could expect his stupid remarks to get. So he was quite pleased with himself, at least for a few seconds before he caught sight of Koushirou's expression; his roommate looked stunned, eyes wide and face pale, staring at something over the stage. Taichi didn't even have a chance to follow his gaze before Koushirou had snapped out of it, speaking quickly just as students began yelling once again.

"It's a Digimon!"

Taichi, Sora, Mimi, and Yamato whirled in the direction of the stage, training their lights on it and not quite sure what they were expecting to see—other than, presumably, a Digimon—but still shocked at the scene before them. It wasn't just a Digimon, it was a massive one; Gigadramon, Taichi distantly registered, the giant dragon-like creature curled up on the stage like a snake that was just waking up from a nap. The lecturer was fortunately better at running than at public speaking, taking off down the rows of seats with a panicked shout, as the Gigadramon spread its wings and prepared to take off.

"Everyone get down!" Taichi shouted, as loud as his voice would carry, Yamato's own similar order coming only a moment later. The students, to their credit, threw themselves down on the ground immediately just as the Gigadramon took off, the Digimon seemingly uninterested in the humans around it as it blasted through the ceiling and into the dark sky.

For a few seconds there was no sound except for the storm, everyone in the now cold and wet lecture hall stunned into silence, and once again it was Taichi's voice that cut through the air first.

"I told you we shouldn't have come to this class."

Koushirou's protest was immediate, even if he couldn't quite match Taichi's volume. "It was mandatory!"


End file.
